How to relate defects and classes of photovoltaic solar panels?

Tipologia de Defeitos em Painéis Solares

The classification of photovoltaic solar panels according to their quality has been established to help consumers make an informed decision, the classification takes into account the defects that occur during the production process of the panels, which will affect their final value.

Why the classification of photovoltaic solar panels?

The component that most affects the cost of a photovoltaic solar panel is the solar cells, which represent about 60% of the final value of a photovoltaic solar panel.

Solar cells are the first component that manufacturers are working on to lower the final price of a solar panel. So this is an important part of classifying the quality of a solar panel…because by reducing the number of solar cells you reduce its quality.

The current market has difficulty guaranteeing class B solar cells. This type of cells is used by test grade photovoltaic power producers, or low cost photovoltaic power producers to lower the cost of a photovoltaic panel.

Factors that influence the valuation of solar panels

The classification of solar panels is carried out by the manufacturers depending on the type and degree of existing defects.

This rating runs from A to D and initially they only considered their performance, but they have updated the rating with different levels for their physical flaws.

There is a lot of confusion between the different types of solar cells. Each defect is usually classified as B, but correct classification is complicated, because there can be dozens of different defects in solar cells.

When the panel is rated, it means that the manufacturer has tested every cell in the solar panel to determine its efficiency. It is this classification that allows manufacturers to adjust the production process and produce cells with a constant efficiency.

With the standardization and efficiency of production processes for all types of photovoltaic panels, the classification system is no longer necessary.

What is the classification of solar panels?

Each photovoltaic solar panel is rated based on its performance and whether or not it has physical defects.

Physical defects that can be found in the panels:

  • Scratched frame, glass or back
  • Dents in the frame or backing
  • Microcracks in solar cells
  • bubbles in the glasses
  • Irregular adhesion between glass and frame
  • Gaps between glass and frame
  • Yield below specifications

The best classification of photovoltaic solar panels has to do with the solar cell type, so the best one is “Class A??

Depending on the severity of the defects found, the solar cell can be classified between “Grade B“The”Grade D?? Since cells with this rating may have a lower total power than expected, they are still a good alternative to save money on your electricity bill.

Class A solar cell class

These solar cells have no visible defects and the electrical data correspond to the specifications.

The manufacturer’s specifications can be checked with cell testing equipment.

However, the class A cell may show a slight variance in staining. But it is not this color deviation that will affect the performance of the solar panel.

Typology of defects in solar cells
Class A solar cell – Image source:

Class of Class B solar cells

These solar cells already have small visible defects, but little impact, and the electrical data is in accordance with the specifications.

Some of these more common visible data include:

  • Slight curvature from 2.0mm to 2.5mm
  • Color deviation, where the visible yellow area covers more than ¼ of the total surface
  • Missing prints
  • Absence of front collector busbar (missing area ≤ L: 0.5 mm × L: 5 mm)
  • Paste leakage (for an area: 0.3 mm – ≤ 2.0 mm2)
  • Risks (between 15 and 50 mm in length)
Typology of defects in solar cells
Class B solar cell – Color change – Image source:

Class of Grade C solar cells

These solar cells have small visible defects and the electrical data no longer corresponds to the specifications.

All solar cells with more defects than class B are classified as class C. Or when the solar cell is partially damaged, it can be cut and used in smaller parts.

Typology of defects in solar cells
Class C solar cell – Lack of segment at busbar – Image source:
Typology of defects in solar cells
Class C solar cell – Watermark – Image source:

Class of Grade D solar cells

A class D solar cell is damaged and cannot be cut to be used in smaller parts, there is nothing to do with this type of solar cell.

They are considered low quality cells.

Typology of defects in solar cells
Class D solar cell – Damaged without the ability to cut – Image source:

Class A solar panels

Class A photovoltaic solar panels are a high-end type of panel.

They have a lower cost per watt and higher efficiency than their cheaper counterparts. They also have a superior warranty and longer life expectancy, so they can be an excellent option for your home or business.

In addition, they have no visible defects, such as missing collection box, or prints, scratches, etc…

Why are they more expensive?

Class A photovoltaic solar panels are more expensive because of their more efficient cells than lower grades, and they have a higher warranty.

Most of these panels have an average life of more than 25 years, while the cheapest are between 15 and 20 years before being replaced.

Grade A solar panels are an excellent choice for anyone looking to save money in the long run.

The option of a lower cost photovoltaic solar panel may be an option for those who want a lower initial cost but require more maintenance over the lifespan.

Advantages of class A photovoltaic solar panels

In addition to a longer average lifespan and higher efficiency, there are other reasons to choose this type of panel.

  • They are produced with high-quality silicon cells, which extend their lifespan.
  • They have a longer warranty from the manufacturer. Your purchase will soon be insured for a longer period of time.

Disadvantages of class A photovoltaic solar panels

The biggest disadvantage of this type of panel is the price!

These usually require a larger initial investment than class B photovoltaic solar panels, but because they are more efficient, they also have a longer average life expectancy.

Class B, C, D, and F panels may not be as efficient or last as long as Class A panels, but they are still a good option for those looking for affordable photovoltaic panels.

What are the options if you cannot opt ​​for class A photovoltaic solar panels?

Although they are the best panels on the market, they require a high initial investment.

So if you don’t have the opportunity to invest in this type of photovoltaic solar panels, you can always choose others… Class B is an excellent option.

Photovoltaic solar panels Grade B they don’t perform as well as the class A ones, but they still have an excellent warranty, almost as long as the class A ones before they need to be replaced.

They are also a cheaper option than class A so have a good benefit. As a rule, they are about 35% cheaper.

The solar cells in a class A photovoltaic solar panel can last up to 15 years before being replaced.

Differences between class A and class B photovoltaic solar panels

The class A photovoltaic solar panel is considered a high-quality product, with a lower cost per watt and higher efficiency. They also have a superior warranty and longer life expectancy, so they may be the best option for your needs.

Class B photovoltaic solar panel already has some defects compared to Class A:

  • Slight bending of the frame
  • color deviation
  • lack of impressions
  • Missing front collector bus
  • mass flight
  • Scratches
  • watermarks

Considering the evidence and key features of each class of solar panels, which one would you choose?

Recommended reading:

Video – Type of defects in photovoltaic solar panels